Invention of Air Conditioning

How one drawing became an industry.

A Different World, Before 1902

The World Before Cool

For most of human history the weather set the terms. Summer closed theaters, slowed factories and cost working days. A hot night was simply a night you did not sleep.

Slide rule

Innovation, November 1881

Slide Rule

Patented in 1881 and manufactured by Keuffel & Esser, Willis Carrier's circular slide rule held a series of scales on a central cylinder; aligned carefully, it delivered the precision of a modern calculator. Carrier used it to calculate dew point control, the breakthrough at the foundation of modern air conditioning.

1902 Schematic drawing of AC system

Innovation, Spring 1902

Lyle's bet

A consulting engineer walked into J. Irvine Lyle's Manhattan office with a client's problem. Humidity at a Brooklyn printing plant was ruining the color register on fine multicolor work, and Judge magazine's schedule was at risk.

Engineers could already heat, cool and humidify air, yet controlling humidity precisely in a factory was something no one had done before. Lyle took the job and gave it to Willis Carrier, a Cornell graduate one year out of school. He was 25 years old.

Painting of printing press

Innovation, July 1902

When was air conditioning invented? The origin of the air conditioner.

Willis Carrier starts the engine driving the world's first modern air conditioning system, installed in the summer of 1902 at the Sackett & Wilhelms printing plant in Brooklyn, New York. This artist's conceptualization appeared in the August 1954 edition of Steelways magazine, which noted that thanks to Carrier, "air conditioning spread through the industry like a cool breeze."

On July 17, 1902, Willis Haviland Carrier designed the first modern air-conditioning system, launching an industry that would fundamentally improve the way we live, work and play. 

Air Conditioner blueprint

October 1903

The Bet Pays Off

On October 21, 1903, Lyle wrote to his home office that "the cooling coils which we sold this company have given excellent results during the past summer." His faith in the opportunity, and in the young engineer who had directed the project, was confirmed.

drawing of air conditioner

What is "conditioning" of air?

Not cooling. Conditioning: washing, drying or humidifying air to a specification. Temperature was one variable among several. Control was the product.

 Blueprint of air conditioned cotton mill

Was it just a paper jam?

Not quite. Humid air made the paper swell between passes, so the colors came out misaligned. Willis Carrier worked out that the fix was controlling the moisture in the room, not the machine. The rest of the century followed from that.

Carrier engineers

Carrier Beginnings

Seven Engineers. One Vision. A Century of Innovation.

On June 26, 1915, Carrier Engineering Corporation was incorporated, with Willis Carrier as president, Lyle as treasurer and general manager, and five hand-picked colleagues. Seven young men scraped together $32,600 in capital and set out, through an economic slump and a world war, to build a brand-new industry. 

A group portrait of Buffalo Forge Company engineers includes Willis Carrier (bottom row, third from right) and his future business partner, J. Irvine Lyle (middle row, sixth from left). Carrier, Lyle and five colleagues would launch Carrier Engineering Corporation as an independent company in 1915. 

Manufacturing space in Newark

The Inspiration

Invention with a Different Intention

Cooling was never the goal. Control was. Everything that followed, from the cold chain to the clean room to the data center, came out of that distinction.

Weathermakers to the World

A name that launched an industry 

Weathermakers to the World

Willis Carrier's life is a study in tenacity and intelligent problem-solving: taking everything that came before him, improving on it, and making something entirely new. 

See how a young man from Western New York created one of the most important inventions of the 20th century. 

More to the story:

History is filled with stories of ingenious people who tried to stay cool before the invention of modern air conditioning. In some warm weather regions of the world, residents constructed homes of thick limestone to reduce indoor heat. In 3000 B.C., an Assyrian merchant devised an evaporative cooler by spraying water on the walls of the basement below his courtyard. Leonardo da Vinci designed a water-driven fan to cool his patron's bedroom while Sir Christopher Wren constructed a gravity exhaust ventilating system for England's House of Parliament. More recently, architects have provided us cooling ideas such as the transom, awning, and sleeping porch. And in every culture, those who could travel to escape the heat sought relief at the shore and in the mountains.  
 
However, not until 1902, when Willis Carrier invented his system of modern air conditioning, would factories and homes be able to provide cool, dry interiors in steamy, hot weather. 

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Explore the Carrier Legacy

Explore the story of Willis Carrier, the history of Carrier Corporation, the invention of modern air conditioning and its impact on the world.